Rolled h-section



Patented Aug. 11, 1931 UNITED STATES PATENT OFFICE'` JAMES H. EDWARDS, OF PASSAIC, NEW

PENNSYLVANIA, ASSIGNORS TO UNITED STATES JERSEY, AND ROBERT A. MARBLE, OF BEN AvoN, STEEL CORPORATION, or NEW Yoan, N. Y., A CORPORATION or NEW JERSEY ROLLED H-SEG'IION Original applicationy med-lay 15,

24, 1929. Serial No. 394,764.

`In a (zo-pending application Serial No. 30,493 filed May 15, 1925, We have described and claimed broadly an invention relating in general to structural members and more particularly to solid rolled sections of substantially or approximately H-shape crosssection. i

In said application We have broadly claimed/a rolled structuralsection having a flange Width greater' than the depth of section and a fiange thickness greater .than its web thickness and said greater flange width and `fiange thickness resulting in a distribution of metal, at such points as to provide a lo maximum section modulus per pound of integral rolled section. 'We have also described and specifically claimed sections of definite proportions. 4 The present application is a division of the above application and aims to'cover a specific design of tial H-shaped cross-section and having Width ot' approximately fourteen inches,- a depth of approximately twelve inches and -Weigh' ing about 100 pounds per linear foot.

The invention is illustrated in the single figure which is a cross sectional vievi1 of a rolled member embodying invention.

The invention aims to provide asolidv rolled H-section having a mean Harige thickness greater than its web thickness, that will have a greater' strength to resist flexure in a direction parallel to its width and subjected axial compression, or to combined compression and bending, than any such rolled section of the same Weight and width, or of the same Weight and depth heretofore put on the market; or, conversely, the produc-tion of such section with less Width, or less depth, than any hitherto ofl'cred rolled section of the same weight or With the same strength in the aforesaid direction.

As explained in the aforesaid application 30,493 Whichever of the purposes (or combination of purposes) stated above may be desired, is accomplished under our invention by making the Width of the solid rolled section (as measured across its flanges) considerably greater than its depth (as meas'- ured between the outer faces of its flanges).

rolled section of substan-` It is Well known that the strength o a section to resist compression is measured by its minor radius of gyration,. and that its strength to resist bending is measured by its maj or section modulus.A f

The novel section embodying our invention vand shown in the accompanying draw ing is 12.348 'inches deep, 14 inches wide;

having a web 0.501 inch thick, a mean flange thickness of 0.851 inch, and Weighing 100 pounds per linear foot. Its minor radius of gyration (about its vertical axis) is 3.58 inches, which is 0.358 per pound. Its major section modulus (about its horizontal axis) -is 135 37 inches cubed.

The nearest section to this, as regards depth and weight, that Awe have been able to .find already on the market is an old H-'section 12.375 inches deep, 12.12 inches Wide, havingla web 0.59 inch thick, a mean flange thickness of 0.937 5 inch,` and weighing 99.33 pounds per linear foot. Its minor radius of gyration is 3.06, which is 0.0308 per pound. Its major section modulus is 129.6, which is 1.305 r pound.

If, 1n order to be exactly comparable with our invention, this old section were modiied by making its web 0.501 inch thick, and by making its Weight' 100 pounds per linear foot, its external dimensions remaining unchanged, its mean fiange thickness would have to be 0.986 inch. Its minorradius of gyration would be 3.12, and its major section modulus would be 133.43.

Ifthe old section Were similarly modified,

but so as to be producible from the same l rolls, that is to say with its internal dimensions remaining unchanged, it would have to be 12 483 inches deep and 12.031 inches Wide, with a mean fiange thickness of 0.991 inch. Its minor radius of gyration would be 3.10 inches, and its major section modulus would be 133.95.

Thus it will be seen that our improved section, although slightly shallower than the old section or than either of its modifications, has a minor radius ot gyration which is 16 percent greater than that of the old section, 14.7 percent greater` than the first modification, and 15.4 percent greater than the second modification. Also that our im.- proved section has a major section modulus which is 3.75 percent greater than that of the old section, 1.45 percent greater than the firs-t modification, andl V1.06 per cent greater thanthe second modification.

When a beamis properly braced laterally its section modulus is the criterion of its strength to resist lexure. If, however, itis not feasible to provide adequate lateral bracing all standard specification stipulate that the working unit stress, by which the section modulus is to be multiplied in order to ascertain the' resistance of the beamv to dexure, shall be reduced by an amount that varies with the ratio of the unbraced length of the beam to this Width. n such cases it is evident that the reduction in allowable Working stress for our section is less than in the case of the old narrower section and consequently the available strength oi? our section is still greater.

Though We have described our invention with particular reference to hbeams and columns of specific proportions and definite dimensions, it is not to be construed that We are limited thereto as certain ranges of variation can be resorted to by those skilled in the art Without departing from the invention as pointed out in the appended claims.

What We claim is:

l. A rolled metal section ol substantially or approximately H-shape in cross-section having substantially the following dimensions, depth 12.3 inches, Width 14 inches, web .5 inch thick and llanges .85 inch thick.

2. A rolled steel section of substantially or approximately H-shape in cross-section havin" the following dimensions, depth 12.348 inches, width 14 inches, web .50i inch thick, the` lianges having slope and each having a mean thickness of .851 inch, the section weighing pounds per linear foot.

3. A rolled steel section of substantially or approximately H-shape in cross;section having substantially the following dimensions, depth 12.348 inches, Width 14 inches, web .501 inch thick,l the flanges having a thickness of .851 inch, the section Weighing 100 pounds per linear foot.

In Witness whereof We have hereunto signed our names.

JAMES H. RDW' ROBERT A.

Lemma 

